Air heating fireplace



March 30, 1965 J. 1.. SUTTON AIR HEATING FIREPLACE :5 Sheets-Sheet 1 Filed Dec. 18, 1962 INVENTOR. James 1.. 34121 01 BY 6W 1;

ATrakNEY J. L. SUTTON AIR HEATING FIREPLACE March 30, 1965 3 Sheets-Sheet 2 Filed Dec. 18, 1962 IN V EN TOR. JZQm es .1: SuZZOIZ 14 TTakA/E'Y March 30, 1965 Filed Dec. 18, 1962 J. L. SUTTON 3,175,552

AIR HEATING FIREPLACE 3 Sheets-Sheet 3 8; m @47 NEUTRAL- 33 69 qg; n -'70 F 1 g. E:

INVENT OR JAM ES L. SUTTON ATTORNEY United States Patent Ofiice 3,175,552 Patented Mar. 30, 1965 3,175,552 AIR HEATING FIREPLACE James L. Sutton, 1101 Kent St., Portsmouth, Ohio Filed Dec. 18, 1962, Ser. No. 245,623 13 Claims. (Cl. 126-121) This invention relates to space heaters and, more specifically, to a combined fireplace and space heater.

It is the principal object of my invention to provide a heater having the general appearance and utility of a fireplace of conventional type but which, in addition can be used as desired to heat one or more rooms of a house, for example, with or without benefit of heat from fuel burning in the fireplace.

Another object is to provide a combined fireplace and space heater as in the precding paragraph, wherein heat from fuel burning in the fireplace may be used to augment or to supplement, heat generated by electrical heater units and forced to one or more rooms through ducts communicating with the fireplace.

Another object is to provide a fireplace-space heater unit which can be selectively used either as the usual fireplace or purely as a heater of space outside the room in which the fireplace is located. When so used, purely as a space heater, heat from burning fuel may alone be sufiicient under moderate heat requirements and is automatically supplemented, as required, by energization of 'one or more electrical heater units.

Still another object is to provide a space heater unit of the type aforesaid, which is prefabricated and readily installed, eflicient in utilization of heat, outwardly attractive in appearance, and versatile in use.

The foregoing and other objects and advantages are attained by providing a fireplace unit, preferably fabricated of sheet metal and having, in addition to the usual fireplace space and opening, chambers at the right and left 'of the opening and out of direct communication with the fireplace space. A tubular element is horizontally positioned within the top or upper portion of the fireplace space and connects the aforesaid chambers so that (1) air may pass from one chamber to the other, through said tubular element, (2) combustion gases from fuel burning in the fireplace space, pass over and about the tubular element on their Way to the chimney and, by conduction, heat air in and passing horizontally through the element, (3) electrical heating units within the tubular element may be used as desired, to supply additional heat directly to the air passing through the element. Alternatively, of course, the electrical units may be efficiently used alone to heat the room in which the fireplace unit is located, or rooms remote therefrom, independently of any heat from fuel in the fireplace space. Auxiliaries such as thermostats, relays, powerdriven blower and control circuits are provided for the automatic control of heat from the electrical units, and to augment the eificiency, utility and convenience of the invention.

Describing in detail the presently preferred form of the invention, in connection with the accompanying draw- FIGURE 1 is a front elevation of the heater and fireplace;

FIGURE 2 is a cross section taken in a plane identified by the line 22 FIGURE 1;

FIGURE 3 is a detail sectional view 'of the plenum or header, taken in a plane identified by line 3-3, FIG- URE 1;

FIGURE 4 is a perspective view of the heater element, with trimmings removed, and partly broken away to show interior details of construction;

FIGURE 5 is a vertical longitudinal section showing the arrangement of heater elements, blower and controls;

FIGURE 6 is a broken horizontal cross section taken in a plane identified by line 6-6, FIGURE 5;

FIGURE 7 is a vertical transverse sectional detail through the heater, as indicated by line 7-7, FIGURE 5; and

FIGURE 8 is a wiring diagram for the electrical heater, blower motor, draft motor, and controls.

Referring in detail to the drawing, 1, FIGURE 1, indicates the floor of a room or basement and supporting the heater fireplace generally identified at 2. From this figure it is noted that the invention has the general appearance of a conventional fireplace, including mantel 3 and central fireplace space 4 within which are positioned the usual andirons or gas log, generally indicated at 5.

Referring to FIGURE 2, 6 identifies the wall at the rear of the fireplace and 7 the sheathing at the front. It will be understood that the mantel 3 and sheathing 7 may be brickwork or prefabricated ornamental sheeting of any desired appearance such as that simulating brickwork, tiling, etc. A heat shield 8 of heat-resisting refractory material may be shaped, sized and positioned to cover and protect all or a portion only, of heated metal walls otherwise exposed to flame and hot gases from burning fuel.

The heater structure is shown in perspective in FIG- URE 4 and is generally identified at 9 and there shown to be a pre-fabricated, built-up form of sheet metal having a base plate 10, back wall 11, right and left end walls 12 and 13, respectively, and top 14 having therein a central opening 15 for connection with a smoke pipe 16.

Within these walls as identified in the preceding paragraph there are positioned right and left, vertical, rectangular sheet metal partitions 17 and 18. As will be clear from inspection of FIGURES 4 and 6, each partition is spaced inwardly from, and in parallel relation with, its respective end walls 12 and 13 and, of course, is fabricated to be integrally united, as by welding, with bottom rear, and top walls 10, 11 and 14, respectively.

At the front a rectangular auxiliary front wall section 19 has a width to extend from the contiguous front edge of top 14, downwardly so that its lower edge defines the top of fireplace opening 4. From FIGURE 4 it will be noted that front wall section 19, in conjunction with top Wall 1.4 and back wall 11, defines an in verted, horizontal channel-shaped passage within which there is fixed a casing 20 of an electric heater unit generally identified at 21, FIGURE 7, and subsequent ly described in detail. Reference to FIGURES 4 and 7 shows that this casing is conveniently oval in transverse vertical section. However, the precise cross sectional form of the casing is not critical, and it may be square, rectangular or other shape.

As is clear from FIGURE 5, casing 20 has a length equal to the horizontal spacing between partitions 17 and 18. These partitions have transversely-aligned openings in their upper area, shaped to receive with a smooth fit, the ends of casing 20. The seams or joints thus formed are sealed fluid-tight, as by welding, so that casing 20 is rigidly mounted as an integral part with the partitions, and forms the sole communication between the space between end wall 12 and partition 17 at the right, and the space between end wall 13 and partition 18 at the left.

At the right, as best shown upon FIGURES 4 and 5, the space between end wall 12 and partition 17 is divided by a horizontal plate 25, to form an upper compartment for a blower 25 driven by a motor 27 through belt 28. The base of the blower is shaped and disposed to extend over, and close, the right end of heater casing 20 so that the blower when in operation, draws in air and impels it through its base, horizontally through the casing, over the heating units therein and into the space at the left between wall 13 and partition 13. As shown, the motor is conveniently bolted to plate 25. The inner periphery of the right end of casing 26 may have an inwardly-directed flange 25V welded or otherwise secured thereto and to which the base 24 of blower 26 is bolted to form a pressure-tight joint. As shown at FIGURE 1, the front of the space above plate 25 and between wall 12 and partition 17, is closed by a door 30 removably held in place by pressure locks or spring catches of known type and hence not shown. This door may be a combined grill and filter wherein the filter element such as one of fiber-glass, is removably and replaceably attached to the inner side of the door, over the grill openings therein, so that all air drawn in by. the fan must first pass through the filter. Alternatively the grill and filter may be in end wall 12. Likewise, a second door 32 is removably positioned beneath door 30, FIGURE 1, to close the space below plate 25 between end wall 12 and partition 17. Doors 36 and 32 may be replaced by a single door removably held in place by spring locks or catches. In such case, of course, the filter element and air inlet openings will be in the up per portion only of the door. As indicated at FIGURE 5, the wall 17 in the space below plate 25 supports main switch 33, relay casing 35, and box 98 housing control parts of the electrical heating system, as well as other accessories for the mechanical and electrical control of the heater units and blower motor, all subsequently described.

At its left end, casing 26 opens into a space formed by end wall 13, partition 18, top 14, back wall 11 and front panel portion 19a, so that all air impelled through the easing is directed into and downwardly through this space. Top and bottom bafiles 20a and 26b, FIGURES 4 and 7, are provided at the left end of the casing as viewed upon FIGURE 5. Other vertical and relatively narrow bafi'les, not shown, may be provided along the front and rear sides of the casing, both coplanar with 20a and 26b. The aforesaid space is completely enclosed except for its lower end where it is in communication with a plenum or header 36 which, as shown, is a parallelepipedal sheet metal structure located below floor level and provided with ducts or outlets 37, 38, 39 in its respective vertical walls and which lead beneath the floor or under the building, to various rooms of a house or other structure, to supply heated air thereto. Header 36 may be formed as an integral part of the fireplace structure or it may be fabricated separately and det-achably secured thereto during installar tion of the invention. From FIGURE 2 it is noted that heated air and products of combustion from fuel or gas logs 5, pass upwardly over and exteriorly about casing 20, thence to smoke pipe 16, thus heating the surface of the casing and supplying heat to the air impelled therethrough by blower 26, in addition to that supplied by the electrical heating units within the casing. Longitudinally and/or circumferentially disposed fins, not shown, may be attached to the casing, exteriorly thereof, to increase the rate of heat exchange.

Smoke pipe 16 is shown at FIGURES 1 and 2, provided with a branch inlet 40 within which is located a combined fan and motor assembly 41 and which, as subsequently described, is used when secondary or auxiliary fuel is being burned, in order to assure added draft when necessary.

Although the number of heating units or coils within casing 20 and the capacity of each, will vary in accordance with the maximum required heat output of each installation, I have shown five such units of kw. capacity each and identified at 42, 43, 44, 35, and 45, respectively, FIGURES 5 and 8. As clearly shown upon FIGURE 7, each unit consists of a central support 47, and side supports 48 and 49, all of dielectric refractory material and fixed in vertical, horizontally-spaced relation to a horizontal center plate 5%. This plate may simply rest upon side stringers 51 and 52 fixed to and extending horizontally along the respective inner vertical walls of casing 219. Thus, by removal of end wall 13, for example, the entire heating element assembly may be horizontally moved into or out of casing 29 for inspection, repair, or replacement of units. Alternatively, an opening, not shown, may be formed in the upper area of end wall and of a size to permit removal of the heater assembly. In this event a cover likewise not shown, will be removably secured over the opening. The five heating units previously identified are preferably alike and of equal capacity and are individually mounted upon and removably carried by plate 50, each in a respective one of five vertical planes preferably uniformly spaced along the length of the casing. As shown, each unit consists of four pairs of coils identified from bottom to top by numerals 53, 54, 55 and 56. The coils of each pair are separated by plate 47 so that each coil is fully supported at both ends.

As. viewed upon FIGURE 7, the left coils of pairs 53 and 54 are electrically connected, as are the corresponding coils of pairs 55 and 56. Likewise, the right ends of right coil pairs 54 and 55 are electrically connected by jumper 42a, as are the corresponding ends of the coils of pairs 53 and 56, by jumper 42b. Leads 420 and 42d connect these jumpers, respectively, with line 71 and control switch '72, subsequently described in connection with the wiring diagram of FIGURE 8.

Referring more particularly to FIGURE 8, the blower motor 27 has previously been identified. This motor is connected from the ll5-volt terminal through lead 57 to one terminal of the motor, thence by lead 58 to the main switch of blower relay and lead 78, to junction 79 with lead 8d of the second one 43 of the five electrical heating units previously described and identified at 42, 43, 44-, and 46. The solenoid 35a of relay 35 is in low-voltage circuit with heater or fireplace thermostat 31 located within casing 20 as shown upon FIGURE 5, as will be subsequently described in detail.

Each of the aforesaid heater units is separately and individually controlled by a respective one of five normallyopen switches or circuit closers 72, 73, 74, 75 and 76. Each switch is positioned to be closed by a respective one of five cams 59, 6d, 6d, 62 and 63. These cams are rotatably adjustably fixed to a common shaft 64 which is connected through a clutch 65 with the shaft of a timing motor or torquer 66. A spring 67 shown as of spiral coil type, has one end fixed to a convenient part of the instrument and the other end attached to shaft 64. The

spring is pre-stressed to urge shaft 64 and the cams fixed thereto, into position permitting opening of all switches '72 through 76. On the other hand, with clutch 695 closed, energization of torquer 66 effects rotation of the shaft and cams as a unit, to sequentially close the switches. Thus, as shown, rotation of shaft 64 in the direction indicated by the arrow, first closes switch 72 to thereby energize heater unit 42, followed at predetermined equal intervals of time, by closure of switches 73, 74, 75 and 76, in succession. When switch 73 is closed, assuming room thermostat 82 is calling for more heat, the circuit through blower motor 27 is closed to thereby initiate forced draft through casing 2t and ducts 37, etc. into the rooms to be heated. When clutch 65 opens, as subsequently explained, shaft 64 is disconnected from timer 65 and spring 67 immediately acts to open all switches 72 through 76. It will be noted that the cams are so shaped that switch 72, for example, remains closed despite continued rotation of shaft 64 to sequentially close switches 73, 74, 75 and 75. Thus when switch 76 becomes closed, all heater units are energized and supplying heat. Suitable means are provided to limit rotation of shaft 64- between limits (1) wherein switch '72 is just open and (2) wherein switch 76 is closed. For example, as indicated at FIGURE 8, such means may take the form of a lever 63 adjustably fixed to shaft 64, and a pair of stops a9 and fixed to any convenient part of the instrument and so disposed as to be engaged by lever 68 when the shaft is at the correspondingly correct limit of rotation.

Continuing reference to FIGURE 8, each heater unit is connected in series with its switch, between the lines 97 and 71 between which there is, for example, a 230-vo1t differential. Thus, one terminal of heater unit 46 is connected by lead 95 with line 71 and its other terminal is connected by lead 95, through switch 76 to line 9'7.

The primary 8th: of a step-down transformer 86 is connected from the neutral line 93, a central tap off the 230- volt source to give the desired 115 volts, and lead 94, to line 71. Fireplace thermostat 8!. has been previously mentioned and described as being located within casing 29. Referring to FIGURE 8, this thermostat is shown to comprise a heat-responsive bellows device connected with a switch bar 810 adapted under normal operating temperatures to bridge and electrically connect the contacts of switch 81b. However, on rise of temperature in casing Ztl to a sufficiently high value, bellows 8i expands to an extent which moves switch bar 81.0 downwardly to open normally-closed switch 81b and to engage and electrically connect the contacts of switch 81a.

Opening and closing of clutch 65 is under control of a solenoid $7 whose armature is connected with one end of a lever 89. This lever is centrally pivoted at 91) to any convenient part of the instrument. The other end of the lever is forked to ride within a circumferential channel of one element of clutch d5.

Blower relay 35 has been previously mentioned and appears upon FIGURE 8, together with its solenoid winding 35a, armature 35b and switch bar 350. When solenoid 35a is energized, armature 35b and switch bar 35c connected therewith are moved upwardly to bridge and electrically connect the relay contacts, thereby completing the circuit from blower motor 27 up to switch '73, When the latter switch is closed in continued operation of torquer 66 the circuit through motor 72 is completed between lines 93 and 9'7.

The electrical connections are such that with switch 8112 closed and room thermostat 82 calling for heat, parallel circuits are closed from transformer secondary Sill; through torquer d6, clutch operating solenoid 87 and relay solenoid 35a. Thus, starting with the left terminal of transformer secondary 8012, as viewed upon FIGURE 8, the circuit extends through lead 86, torquer 66, lead 86a, switch 811;, room thermostat '32, and leads 82a and 83 to the other terminal of secondary 8%. The circuit through solenoid 35a of blower relay 35 is traced from leads 86, 86b, solenoid 35a, lead 86c, to thermostat 82 and lead 32c to secondary 8011, as previously traced.

However, when as the result of a sufficiently high temperature in casing 26), thermostat 81 opens switch 811; and closes switch Ella, the circuits through torquer 66 and clutch solenoid 37 are opened. Clutch 65 opens and spring 67 returns shaft 64- and its cams 59 through 63 to the open positions shown, thus opening switches 72 through 75. Closure of switch 31:: maintains a circuit through solenoid 35a of blower relay 35, by way of leads 86, 86b, coil 35a, switch Ella and lead 821') to secondary 8%. Thus the blower remains in operation as long as switch 81a is closed, even although room thermostat 32 is not calling for heat. Heater coil 43 has a high impedancerelatively to blower motor 27 so that the latter does not become operative until switch '73 closes. Of course, if thermostat 82 is at this time calling for heat, a parallel circuit remains effective through solenoid 35a, lead demand solenoid $2. Thus excessively high temperatures within casing are prevented. Bellows 81 may be replaced by other known heat-sensitive means such as a bimetallic element. A 1l5-volt branch extends from lead d7 through manually-actuated switch 91 to motor 41 of the draft fan previously described and shown at FIGURE 2, thence by lead 92 to the other side of the line at 93.

It is also contemplated that blower motor 27 may be a three-speed machine, successively higher speeds being cut in by successive closure of switches 72 through 76, so that on closure of switch 76 the blower is operating at maximum capacity.

Operation Numerous ways of use and operation of my invention will be obvious to those skilled in the art after a study of the foregoing description. In fact, its versatility is one of the chief features and advantages.

With main switch 33 closed and heater unit switches 72 through 76 open, as well as clutch 65, when room thermostat 82 calls for heat, solenoid 87 is energized to close the clutch and at the same time motor 66 is energized to initiate rotation of shaft 64 and the cams 59 through 63 fixed thereto. Assuming continued rotation of shaft 64 until arm 68 engages stop 70, switches 72 through 76 are closed in succession. When switch 73 closes, assuming switch 81]; remains closed, motor 27 is energized to start forced circulation of air through casing 20. Under this condition of use, heat from fuel burning in the fireplace supplements that supplied by heater units 42 through 46.

In cases where moderate amounts of heat only are required, switch 33 may be left open and the necessary heat supplied from fuel burning in the fireplace, to heat air within casing 20. Under such use an auxiliary circuit with switch, not shown, may connect blower motor 27, from the right terminal of the motor, to line 97.

While I have disclosed the form of the invention presently preferred by me, numerous changes, substitutions of equivalents and variations will occur to those skilled in the art after a study of the foregoing description. Consequently the description should be taken in an illustrative, rather than a limiting sense; and I desire to reserve all modifications within the scope of the subjoined claims.

I claim:

1. A fireplace and space heater unit comprising, wall means defining a fowardly open fireplace space, in which fuel may be burned to directly supply heat to ambient air through the forward opening therein, duct means to conduct combustion gases from the top of said fireplace space, said wall means also defining forwardly-closed first and second chambers at respective sides of said fireplace space and out of direct communication therewith, a tubular casing horizontally disposed in the upper portion of said fireplace space and connecting said first and second chambers for direct passage of air therebetween, said tubular.

casing being constructed and arranged to be heated directly by combustion gases from fuel burning in said fireplace space passing to said duct means, electrical heating means positioned within said tubular casing, and power driven blower means in one said chamber and operable to impel air between said chambers, through said tubular casing for distribution to space to be heated.

2. In a combined fireplace and space heater, walls defining a central fireplace space with a front opening and in which fuel may be burned, said walls including first and second, vertical, parallel, laterally-spaced partitions forming wall portions, respectively, of first and second chambers at the right and left of said central space and out of direct communication therewith, said partitions having aligned openings in the upper areas thereof, a tubular casing having a central axis and having its ends fitting said openings in gas-tight relation therewith, respectively, and.

passing through the upper portion of said central space, whereby combustion gases from fuel burning therein flow upwardly over and about said casing in passing to a chimney, electrical heater means positioned within and along said casing, and comprising a plurality of heater units spaced along said axis, and circuit means for energizing said units seriately.

3. The device of claim 2, said circuit means comprising a plurality of switches each in circuit with a respective one of said heater units, a shaft, a plurality of cams fixed to said shaft, each said cam being operable to close said switches in responseto rotation of said shaft, a torque motor, connections between said torque motor and said shaft to rotate said shaft in response to energization of said torque motor, and a room thermostat in circuit with said torque motor.

4. The device of claim 3, said cams being fixed to said shaft in positions closing said switches sequentially at predetermined time intervals.

5. In a fireplace and space heater combination, front, top, back, and end walls united to form a generally parallelepipedal structure, first and second partitions fixed in said structure, each in spaced relation With and parallel with a respective one of said end walls to define therewith, first and second chambers and a central fireplace space between said partitions, there being a flue opening in said top Wall for egress of combustion gases from said central fireplace space, the lower area of said front Wall, between said partitions, being removed to define a fireplace opening, each said partition having an opening in its upper area, a tubular casing positioned in the upper portion of said fireplace space and having each end fitting the opening of a respective partition in gas-tight relation therewith, said casing placing said chambers in communication, products of combustion of fuel burned in said fireplace space passing upwardly over and about the exterior of said casing to said flue opening, electric heater means positioned in said casing, and power-driven blower means in one said chamber, operable to induce flow of air between said chambers, through said casing.

6. In a fireplace and space heater unit, a unitary, sheet metal structure forming (a) a forwardly open central fireplace space in which fuel may be burned, (b) two discrete chambers contiguous to and at opposite sides of said central fireplace space, respectively, a tubular conduit connecting said chambers and passing horizontally through the upper part of said central fireplace space and out of direct communication therewith, means forming an outlet for combustion gases opening through the top of said central fireplace space whereby combustion gases from fuel burning in said central fireplace space pass upwardly exteriorly over and about said conduit to said outlet, electric heater means mounted within said conduit, and blower means in one said chamber and operable to impel air from one said chamber, through said conduit and said other chamber in succession for distribution to space to be heated.

7. A combined fireplace and space heating unit comprising, top, bottom, back and end walls secured together along their meeting edges to form a parallelepipedal casing, first and second vertical laterally-spaced partitions within said casing and forming with said top, bottom and back walls, a forwardly-open fireplace space in which fuel may be burned for heating of ambient space, there being an opening through said top wall from said space, for egress of combustion gases, each said partition also forming with said top, bottom, back, and respective end wall, first and second chambers, wall means closing the front of said second chamber, an auxiliary wall closing the upper portion only of the forward opening of said fireplace space, a horizontal tubular conduit extending in and across said fireplace space, behind said auxiliary wall, and having its respective ends sealed in openings in said partitions to place said chambers in communication, power-driven blower means in one of said chambers and operable to impel air from said first to said second chamber, through said conduit, and electric heater means mounted in said conduit.

8. The unit of claim 7, a duct connected with the opening in the top wall of said fireplace space to conduct products of combustion therefrom to ambient air, and an auxiliary draft, power-driven fan connected with said duct to increase the draft therein.

9. In a fireplace and space heater combination, front, top, back, and end walls united to form a generally parallelepipedal structure, first and second partitions fixed in said structure, each in spaced relation with and parallel with a respective one of said end walls to define therewith, first and second chambers and a central fireplace space between said partitions, the lower area of said front wall, between said partitions, being removed to define a fireplace opening, each said partition having an opening in its upper area, a tubular casing positioned in the upper portion of said fireplace space and having each end fitting the opening of a respective partition in gas-tight relation therewith, said casing placing said chambers in communication, products of combustion of fuel burned in said fireplace space passing upwardly over and about the exterior of said casing, electric heater means positioned in said casing, power-driven blower means in one said chamber operable to induce fiow of air between said chambers through said casing, said electric heater means comprising a plurality of heater units in spaced relation in and along said casing, a plurality of normally-open switches each in circuit with a respective one of said heater units, a rotatable shaft, a plurality of cams fixed to said shaft and constructed and arranged to close a respective one of said switches in predetermined sequence in response to rotation of said shaft, a torque motor, a clutch closable to connect said motor to said shaft to rotate the same, electromagnetic means energizable to close said clutch, and a thermostat in circuit with said electromagnetic means and torque motor.

10. The device of claim 9, a motor connected to drive said blower means, and a circuit for said blower means having one terminal connected between a selected one of said heater units and the corresponding switch therefor.

11. The device of claim 9, and spring means urging said shaft in retrograde rotation to open all said switches on de-energization of said electromagnetic means.

12. In a combined fireplace and space heater, a unitary built-up sheet metal parallelepipedal casing comprising top, bottom, back, and end walls, first and second vertical laterally-spaced partitions in said casing each having its to, bottom and back edges secured to said top, bottom and back walls, respectively, to define between them a forwardly-open fireplace space in which fuel may be burned, there being an opening in said top wall from said fireplace space for egress of combustion gases, each said partition defining with said bottom and back walls and its adjacent end wall a chamber out of direct communication with said fireplace space, Wall means covering the front of each said chamber, an auxiliary front wall over the upper portion only of the forward opening in said fireplace space and having its upper and end edges in sealed relation with said top wall and said partitions, respectively, and a tubular conduit having its ends sealed in openings in said partitions respectively and passing horizontally through the upper portion of said fireplace space, behind said auxiliary wall, said tubular conduit being spaced from said top, back and auxiliary walls, blower means in one said chamber and operable to impel air successively from one said chamber, through said tubular conduit, to the other said chamber, and circuit means connected with said other chamber, for conducting air therefrom to space to be heated.

13. The fireplace and space heater of claim 12, and electric heater means mounted within said tubular conduit.

References Cited by the Examiner UNITED STATES PATENTS 1,426,643 8/22 Holmberg 126-116 1,867,740 7/32 Guy 126121 2,015,485 9/35 Lindberg 126121 2,052,643 9/36 Modine 126-121 2,136,559 11/38 Miller 23670 2,231,258 2/41 Elmore 126-121 2,584,326 2/52 Campbell ..l10-162 2,787,997 4/57 Asbury 1261 10 2,993,106 7/61 Maudlin et al 236-1 3,085,564 4/63 Weimer 126-121 JAMES W. WESTHAVER, Primary Examiner. 

12. IN A COMBINED FIREPLACE AND SPACE HEATER, A UNITARY BUILT-UP SHEET METAL PARALLELELPIPEDAL CASING COMPRISING TOP, BOTTOM, BACK, AND END WALLS, FIRST AND SECOND VERTICAL LATERALLY-SPACED PARTITIONS IN SAID CASING EACH HAVING ITS TO, BOTTOM AND BACK EDGES SECURED TO SAID TOP, BOTTOM AND BACK WALLS, RESPECTIVELY, TO DEFINE BETWEEN THEM A FORWARDLY-OPEN FIREPLACE SPACE IN WHICH FUEL MAY BE BURNED, THERE BEING AN OPENING IN SAID TOP WALL FROM SAID FIREPLACE SPACED FROM EGRESS OF COMBUSTION GASES, EACH SAID PARTITION DEFINING WITH SAID BOTTOM AND BACK WALLS AND ITS ADJACENT END WALL A CHAMBER OUT OF DRECT COMMUNICATION WITH SAID FIREPLACE SPACE, WALL MEANS COVERING THE FRONT OF EACH SAID CHAMBER, AN AUXILIARY FRONT WALL OVER THE UPPER PORTION ONLY OF THE FORWARD OPENING IN SAID FIREPLACE SPACE AND HAVING ITS UPPER AND END EDGES IN SEALED RELATION WITH SAID TOP WALL AND SAID PARTITIONS, RESPECTIVELY, AND A TUBULAR CONDUIT HAVING ITS ENDS SEALED IN OPENINGS IN SAID PARTITIONS RESPECTIVELY AND PASSING HORIZONTALLY THROUGH THE UPPER PORTION OF SAID FIREPLACE SPACE, BEHIND SAID AUXILIARY WALL, SAID TUBULAR CONDUIT BEING SPACED FROM SAID TOP, BACK AND AUXILIARY WALLS, BLOWER MEANS IN ONE SAID CHAMBER AND OPERABLE TO IMPEL AIR SUCCESSIVELY FROM ONE SAID CHAMBER, THROUGH SAID TUBULAR CONDUIT, TO THE OTHER SAID CHAMBER, AND CIRCUIT MEANS CONNECTED WITH SAID OTHER CHAMBER, FOR CONDUCTING AIR THEREFROM TO SPACE TO BE HEATED. 